In my above co-pending application I described and claimed a knitting device comprising a needle bed, a plurality of equidistantly spaced substantially parallel needles in the needle bed and a sinker consisting of a shaft having a pair of opposed ends, a hook formed on one of said ends of said shaft, a bushing on said shaft in proximate relation to said hook, said bushing having a tapered leading thread, said thread having a larger root diameter adjacent the hook and a small root diameter as it approaches the other end of the shaft, whereby upon rotation of said sinker and movement of the sinker along the needle bed, working yarn or material can be sequentially drawn from between the needles.
Although the arrangement of the knitting device disclosed in my issued U.S. Pat. No. 3,868,834 is perfectly satisfactory, I have now perfected an improved needle bed which facilitates the operation of the device. The prior arrangement of my issued U.S. Pat. No. 3,868,834, as with all other prior arrangements of which I am aware, contemplates the use of metallic needles whereas with the present invention I propose using needles of plastics material. By using needles made of a flexible plastics material, adjacent pairs of needles may move apart as yarn is drawn from the gap between them and the barbs of the needles may be depressed more easily during the knitting operation. Comparable metallic needles of conventional design have minimal lateral flexibility and would require up to ten times the force to depress their barbs, thus making them unsuitable for light, hand-operated knitting devices such as specified in my present application.
Another improvement in my present needle bed is the inclusion of intermediate depressor plates at intervals which facilitate the depression of the barbs of the needles by providing fixing points for a locking bar intermediate the ends of the bed. This limits the distortion of the bed and permits a light construction.
In prior U.S. Pat. No. 2,239,212 and other simple machines descended from the metal Lee stocking frame, the needle beds' supports and locking bar are of heavy construction owing to the considerable force required to depress all the barbs of the needles at the same time and to avoid distortion of the beds. In my invention, the depressor plates and the plastic needles limit distortion to the degree that the shaft of the sinker may be used as a locking bar.